The use of voice calls is decreasing as many people favour other communication options, such as instant messaging. A difference between voice- and message-based communication is that all users need to participate in the process at the same time for voice communication, while this is optional for message-based communication. In fact, in many people's opinion message-based communication is favoured for this reason, as it does not place any requirements or restrictions on the other participant. As this opinion grows it may well be people become reluctant to use voice-based communication in order to avoid possible intrusion in the other participant's schedule.
However, whilst the use of voice-based communication is decreasing, many people feel that the level of interpersonal engagement is less for message-based communication, and hence a reduction in voice-based communication may exacerbate any existing feelings of loneliness.
If two people want to engage in a voice call, and ensure that the chosen time is convenient for both parties, then the current typical methods to organize the call are:                Use a message based communication to schedule the call, or        Schedule a regular call, perhaps with the use of a calendar or agenda to arrange/track the call times.        
Issues with these current methods include:                While a certain scheduled time for setting up the voice call appeared to be convenient at the time of scheduling, subsequent occurring events may imply that that it is no longer so,        Where a time appears to be convenient in the sense that it does not overlap with other activities, the time may not be the most appropriate for setting up a voice call in that one or both of the participants/parties may not be in the mood for a conversation at the scheduled time.        
Thus a dilemma exists; while use of voice messaging may reduce loneliness, people are becoming increasingly reluctant to engage in a voice call. Hence, despite the fact that a second participant may be a willing participant in the process, this information is unknown to the first participant who is therefore reluctant to make the call.